Lawn trimming device



Oct. 11, 1938. E. A. GAST 2,132,465

` LAWN TRIMMING DEVICE Filed Sept. 22. 1936 2 Sheets-Sheet l oct. 11, 1938. E. A. GAST 2,132,465

LAWN TRIMMING'DEVICE Filed sept. 22, 195s 2 sheets-sheet 2 /ye/z [ai Patented Oct. 11, 1938 UNITED STATES PATENT olf-FICE 14 Claims.

'55 vide an efficient and inexpensive device for the purpose'mentioned, the operation of which will produce, 'with a minimum of expense of time and labor, a clean and neatedge of the grass or similar vegetation along a walk, flower-bed or 10 similar'limiting area.

Further objects of my invention will appear from the following detailed description thereof.

' In the drawings:

Figure 1 is a plan View of a device constructed in accordance with this invention.

Figure 2 is a bottom view of the device.

Figure 3 is a section on line 3 3 of Figure 2.

Figure 4 is a side elevation partly in section to illustrate the drive mechanism.

Figure 5 is a view of a detail.

The numeral I indicates the main cross member of the frame upon which the various operating elements of my device are assembled. In-

`tegrally formed on the ends of' the member I are circular plates 2, the inner central portions of which are provided with bosses 3 3 for stud shafts 4 4 upon which the main carrying and drive wheels 5 5 are rotatably mounted. The inner sides yof the wheels 5 5 are provided with circular recesses of slightly larger diameter than the plates 2 2 so that the wheels' may t over and rotate around said plates. The recesses are provided with internal gears 1.

The frame member I has integrally formed therewith a forwardly and downwardly extending bracket member 8, which terminates in horizontal bifurcations 9 9 which serve as bearings for -a short shaft I0, on the lower end of which a rotatory cutter I I is secured.y The shaft I is adapted to slide vertically in said bearings. Mounted in bearings in the plates 2 2 in front of the frame member I is a transverse shaft I2 upon the ends `of which pinions I3 are xedly secured. The pinions I3, intermesh with the internal gears l in the wheels which are mounted on'the studs 4, so that upon rotation of the wheels the transverse shaft I2 is driven. Fixedly secured on the shaft I2 is a bevel gear I5, which intermeshes with a bevel pinion I6 secured on the shaft [Il between the bifurcations 9 9. Rotation of the wheels 5 5 is thus arranged to drive the cutter The cutter Il is provided with a plurality of blades I1, the cutting edges- I8 of which are adapted to co-act with the edge of a stationary cutter I9 mounted on a bracket 20 which is in- AEll tegrally formed with the inner face of one of the 60 direction. The cutter I9 is disposed in a similar oblique direction `on the bracket however, the angle of inclination of the blades Il f'rom the horizontal is slightly less than that of the fixed blade I9, whereby therels a sharp angle of contactbetween the respective blades I1 and the 5 blade i9 as the cutter II rotates causing a shearing action between the moving and fixed blades; this shearing rotation involves, of course, a slight vertical displacement ofthe rotary cutter which is accommodated` by longitudinal sliding movements of the shaft I9 in its bearings in the bifurcations 9 9. The movable blades are furthermore maintained in effective shearing contact with lthe fixed blade bythe downward component of force during rotation of the drive gear 4 I5 upon the driven gear I6. This downward component of force not only maintains effective shearing contact between the blades but also effects the automatic adjustment of' the respective blades totake care of wear and other conditions.

Integrally formed with the plate 2, oppositethe plate supporting bracket 20, is an arm 2l the free end 22 of which curves inwardly and is provided with a rectangular head 23 which contains a pocket 24 the top and rear sides of which aref25 open. Rotatably mounted on the arm 2| near its Afree end is a wheel 25 which serves as a support for the arm during operation of the device.

A bracket 26 is movably mounted on the transverse shaft I2 by means of perforations in bifurcations 21. The bracket 26 has a rectangular head 28 between the front and rear walls of which a bevel gear 29 is rotatably mounted. The bevel gear 29 intermeshes with a bevel gear 30 xedly mounted on the drive shaft I2. Secured tothe shaft 3l of bevel gear 29 is the shaft 32 of a cylindrical brush 33. The free end of shaft 32 rests in the pocket 24 of head 23 which serves as a bearing therefor supporting the brush 33 in front of the movable cutters Il. By reason of the movable 4mounting of bracket 26 on the shaft I2 the brush 33 is permitted a limited up vanddown movement; during operatiomhoweventhe downward component of force of the drive gear applies a moderate downward pressure to the brush so as to maintain it in contact with a surface over which it is passing for the purpose hereinafter set forth.

The rear portion of the frame member I is provided with a support 34 upon which the de- Avice rests when it is'not in operation. Handle brackets 35 35 are loosely mounted on the transverse shaft I2 and serve as a means for the attachment of an operating handle 36.

The operation of my device is as follows: In Figure 1 the line 31 indicates the edge of a sidewalk along which the lawn 38 is being trimmed. The drive wheels 5, which may be provided with rubber tires39 for the purpose of traction, are located so as to straddle the edge to be trimmed,

.up would not vbe engaged by the cutters.

the left hand drive wheel riding upon the pavement and the Votherfupon'*the'slavvm'""Should there be any great unevenness the operator may, of course, support the device so as to ride effectively only upon the wheel which is on the pavement. The rotation of the drive wheels actuates the cutting blades l1 in the direction of the arrow in Figure 1 this is accomplished by means of the bevel gears l5 and I6. As the mechanism proceeds forwardly the rotating cutter blades thus engage the grass and bring it into contact with the fixed cutter blades where the shearing action of the respective blades severs it. While the rotating cutter l1 may be fairly close to the pavement the edge of which is to be trimmed, there will frequently be grass which lies flatV and which without some means of pick- This pick-up is accomplished by means of the cylindrical brush 33 which rotates in a direction opposite to the rotation of the cutters I1. The brush 33 is so disposed as to pass over in contact with the pavement and the rotation of said brush by means of gears 30 and 29 serves to pick up the grass and carry it into the path of the rotating cutters.

Having thus fully described my invention, what I claim as new andrdesire to secure by Letters Patent is:

1. A trimming device of the character specied comprising a frame, a fixed cutter carried by said frame, a movable cutter carried by and arranged to rotate on a vertical axis slidable in said frame, said movable cutter being arranged to be supported vertically by said fixed cutter, a wheel on which said frame is adapted to ride and means whereby said movable cutter is actuated by the rotation of said wheel tomake shearing contacts with said fixed cutter.

.2. A trimming device of the character specied comprising a frame, a fixedV cutter carried by said frame, aV movable cutter carried by and arranged to rotate on a vertical axis slidable in said'frame, said movable cutter being arranged to be supported by said xed cutter, means whereby said movable cutter is actuated by the movement of said frame to make shearing contacts Ywith said fixed cutter, a non-cutting member movably mounted in said-frame, a wheel on .which Vsaid frame is Vadapted Jto-ride and means vfor the actuation of said member by the rotation of said wheel whereby objects to'be cutrare moved into the path of movement of said movable cutter. v l

3. A trimming device of the character specified comprising a frame, wheels mounted on said frame and arranged to carry same, a fixed cutter carried by said frame, a movable cutter carried by and arranged to rotate on a vertical axis slidable in said frame,'said movable cutter being arranged to be supported vertically by said fixed cutter, and means whereby said movable cutter is actuated by the rotation of said wheels to make shearing contacts with said fixed cutter.

4. A trimming device of the character specied comprising a frame, a fixed cutter carried by said frame, a movable cutter carried by and arrange-d to rotate on a vertical axis slidable in said `frame, said movable cutter'comprisingY a yplurality of radial blades, said movable cutter being arranged to be supported vertically by said xed cutter, a wheelV on which said frame is adapted to Yride and means whereby said movable cutter is actuated bythe rotation of said wheel to cause said blades successively to make shearing contacts with said fixed cutter.

5. A trimming device of the character specied comprising a frame, a fixed cutter carried by said frame, a movable cutter carried by and 5 arranged to rotate on a vertical axis slidable in said frame, said movable cutter comprising a -plurality of radial blades, said movable cutter being arranged to be supported vertically by said xed cutter, a wheel on which said frame is 10 anzlaptedY to ride, means whereby said movable cutter is' actuated by the rotation of said wheel to cause said blades successively to make shearing contacts with said fixed cutter, a non-cutting member movably mounted in said frame, and 15 means for the actuation of said member by the movement of said frame, whereby objects to be cut are moved into the path of rotation of said radial blades. Y 6. A trimming device of the character speci-20 ed comprising a frame, wheels mounted on said frame and arranged to carry same, a fixed cutter carried by said frame, a transverse shaft rotatably mounted in said frame, means whereby the rotation of said wheels is arranged to actu- 25 ate said shaft, a vertical shaft rotatably and slidably mounted in said frame under said transverse shaft, intermeshing bevel gears xedly mounted on said transverse and vertical shafts,

whereby the former is arranged to'drive the 30 latter, and a. movable cutter secured on the lower end of said vertical Yshaft and arranged during rotation to be supported vertically on and to make shearing contacts with said fixed cutter.

7. A trimming Vdevice of the character speci- Y35 fied comprising a frame, wheels mounted on said arranged to actuate said shaft, a vertical shaft rotatably mounted. in said Vframe under said transverse'shaftjintermeshing bevel gears fixedly mounted on said transverse and vertical shafts, whereby the' former is arranged to drive :T45

the latter, a movable cutter secured 0n the lower end of saidvertical shaft and arranged during rotation to be supported vertically on and to make shearing contacts with said fixed cutter,

a non-cutting member movably mounted in said T50 frame, and means for the actuation of said member by the movement of said frame, whereby objects tc be'cut are moved into the path of rotation of said movable cutter.

8. A trimming device of the character specified "5'5 comprising a frame, wheels mounted on said frame and arranged to carry same, a fixed cutter carried by said frame, a transverse shaft rotatably mounted in said frame, vmeans whereby the rotation'o-f said wheels is arranged to actu- 60 ate said shaft, a vertical shaft rotatably and slidably mounted in said frame under said transverse shaft, intermeshing bevel gears xedly mounted on said transverse and vertical shafts, v

whereby the former-is arranged to drive the 6.5

latter, and a Vmovable cutter secured on the lower end of said vertical shaft, said movable cutter comprising a plurality of radial blades which are arranged during rotation to be supported verti- Y cally on and successively to make shearing con- 70 tacts with said fixed cutter. Y

9. A trimming device of the character specified comprising a frame, wheels mounted on said frame and arranged to carry same, a fixed cutter carried by said frame, a transverse shaft rotatably A75 mounted in said frame, means whereby the rotation of said wheels is arranged to actuate said shaft, a vertical shaft rotatably and slidably mounted in said frame under said transverse shaft, intermeshing bevel gears fixedly mounted on said transverse and vertical shafts, whereby the former is arranged to drive the latter, a movable cutter secured on the lower end of said vertical shaft, said movable cutter comprising a plurality of radial blades which are arranged during rotation to be supported vertically on and suc.-

cessively to make shearing contacts with said fixed cutter, a non-cutting member movably mounted in said frame, and means for the actuation of said member by the movement of said frame whereby objects to be cut are moved into the path of rotation of said radial blades.

10. A trimming device of the character specifled comprising a frame, wheels mounted on said frame and arranged to carry same, a fixed cutter carrie-d by said frame and disposed in an oblique plane, a transverse shaft rotatably and slidably mounted in said frame, means" whereby the rotation of said wheels is arranged to actuate said shaft, a vertical shaft rotatably mounted in said frame under said transverse shaft, intermeshing bevel gears xedly mounted on said transverse and vertical shafts whereby the formery is arranged to drive the latter, and a movable cutter secured on the lower end of said vertical shaft, said movable cutter comprising a plurality of radial blades, said blades being disposed in a plane slightly less oblique than said fixed cutter and being arranged during rotation to be supporte-d vertically on and successively to make shearing contacts with said fixed cutter.

11. A trimming device of the character specified comprising a frame, wheels mount-ed on said frame and arranged to carry same, a fixed cutter carried by said frame and disposed in an oblique plane, a transverse shaft rotatably mounted in said frame, means whereby the rotation of said wheels is arranged to actuate said shaft, a vertical shaft rotatably and slidably mounted in said frame under said transverse shaft, intermeshing bevel gears flxedly mounted on said transverse and vertical shafts whereby the former is arranged to drive the latter, a movable cutter secured on the lower end of said vertical shaft,

' said movable cutter comprising a plurality of radial bla-des, said blades being disposed in a plane slightly less oblique than said fixed cutter and being arranged during rotation to be supported vertically on and successively to make shearing contacts with said fixed cutter, and a non-cutting member movably mounted in said frame, and means for the actuation of said member by the movement of said frame, whereby objects to be cut are moved into the path of rotation of said radial blades.

12. A trimming device of the character specified comprising a frame, wheels mounted on said frame and arranged to carry same, a fixed cutter carried by said frame, a transverse shaft rotatably mounted in said frame, means whereby the rotation of said wheels is arranged to actuate said shaft, a vertical shaft rotatably and slidably mounted in saidl frame under said transverse shaft, intermeshing bevel gears fixedly mounted on said transverse and vertical shafts, whereby the former is arranged to drive the latter, a movable cutter secured on the lower end of said vertical shaft and arranged during rotation to be supported vertically on and to make shearing contacts with said fixed cutter, a bracket loosely mounted on said transverse shaft, a third shaft rotatably mounted in said bracket, intermeshing bevel gears mounted respectively on said transverse and third shafts,whereby the latter is driven in reverse direction to the rotation of said vertical shaft, a brush operatively secured to said third shaft in front of said movable cutter, whereby upon rotation of said brush objects to be cut are moved into the path of said movable cutter, and means for supporting the free end of said brush.

13. A trimming device of the character specified comprising a frame, wheels mounted on said frame and arranged to carry same, a fixed cutter carried by said frame, a transverse shaft rotatably mounted in said frame, means whereby the rotation of said wheels is arranged to actuate said shaft, a vertical shaft rotatably and slidably mounted in said frame under said transverse shaft, intermeshing bevel gears fixedly mounted on said transverse and vertical shafts, whereby the former is arranged to drive the latter, a movable cutter secured on the lower end of said vertical shaft, said movable cutter comprising a plurality of radial blades which are arranged during rotation to be supported vertically on and successively to make shearing contacts with said fixed cutter, a bracket loosely mounted on said transverse shaft, a third shaft rotatably mounted in said bracket, intermeshing bevel gears mounted respectively on said transverse and third shafts, whereby the latter is driven in reverse direction to the rotation of said vertical shaft, a brush operatively secured to said third shaft in front of said movable cutter, whereby upon rotation of said brush objects to be cut are moved into the path of said movable cutter, and means for supporting the free end of said brush.

14. A'trimming device of the character specified comprising a frame, wheels mounted on said frame and arranged to carry same, a fixed cutter carried by said frame and disposed in an oblique plane, a transverse shaft rotatably mounted in said frame, means whereby the rotation of said wheels is arranged to actuate said shaft, a vertical shaft rotatably and slidably mounted in said frame under said transverse shaft, intermeshing bevel gears fixedly mounted on said transverse and vertical shafts whereby the former is arranged to drive the latter, a movable cutter secured on the lower end of said vertical shaft, said movable cutter comprising a plurality of radial blades, said blades being disposed in a plane slightly less oblique than said fixed cutter and being arranged during rotation to be supported vertically on and successively to make shearing contacts with said fixed cutter, a bracket loosely mounted on said transverse shaft, a third shaft rotatably mounted in said bracket, intermeshing bevel gears mounted respectively on said transverse and third shafts, whereby the latter is driven in reverse direction to the rotation of said vertical shaft, a brush operatively secured to said third shaft in front of said movable cutter, whereby upon rotation of said brush objects to be cut are moved into the path of said radial blades, and means for supporting the free end of said brush.

ERNEST ALBERT GASIl 

